Effect of 3C-SiC Irradiation with 8 MeV Protons

2017 ◽  
Vol 897 ◽  
pp. 311-314 ◽  
Author(s):  
Alexander A. Lebedev ◽  
Boris Ya. Ber ◽  
Gagik A. Oganesyan ◽  
Sergey V. Belov ◽  
Natalia. V. Seredova ◽  
...  
Keyword(s):  
Silicon Carbide ◽  
Hall Effect ◽  
Proton Irradiation ◽  
Removal Rate ◽  
Initial Concentration ◽  
A Value ◽  
Full Compensation ◽  
Mev Protons

Effects of proton irradiation in n-3C-SiC grown by sublimation on a 4H-SiC substrate have been studied by the Hall effect and photoluminescence methods. It was found that the carrier removal rate (Vd) reaches a value of ~110 cm-1. The full compensation of samples with an initial concentration of (1-2) x 1018 cm -3 was estimated to occur at doses of about 6 x 1015 cm -2. Compared with 4H and 6H silicon carbide, no significant increase in the intensity of so-called "defective" photoluminescence was observed in 3C-SiC.

Conductivity Compensation in CVD-Grown n-4H-SiC under Irradiation with 0.9 MeV Electrons

2015 ◽  
Vol 821-823 ◽  
pp. 293-296
Author(s):  
Vitalii V. Kozlovski ◽  
Alexander A. Lebedev ◽  
Elena V. Bogdanova ◽  
Natalia. V. Seredova
Keyword(s):  
Electron Irradiation ◽  
Removal Rate ◽  
Initial Concentration ◽  
A Value ◽  
Compensation Mechanisms ◽  
Capacitance Voltage ◽  
Full Compensation ◽  
Defect Luminescence

Effects of electron irradiation in n-4H-SiC have been studied by the methods of the capacitance--voltage characteristics and photoluminescence. It was found that the carrier removal rate (Vd) reached a value of ~0, 25 cm- 1. Full compensation of samples with an initial concentration of 1.2 1015cm-3was observed at doses of about 5 1015cm-2. Simultaneously with the increase in the degree of compensation, the intensity of the “defect luminescence”, typical of 4H SiC, became higher. The physical compensation mechanisms were analyzed for the samples under study.

scholarly journals Radiation Defects in Heterostructures 3C-SiC/4H-SiC

Crystals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 115 ◽  
Author(s):  
A.A. Lebedev ◽  
G.A. Oganesyan ◽  
V.V. Kozlovski ◽  
I.A. Eliseyev ◽  
P.V. Bulat
Keyword(s):  
Silicon Carbide ◽  
Hall Effect ◽  
Proton Irradiation ◽  
Removal Rate ◽  
Structural Defects ◽  
Radiation Defects ◽  
Photoluminescence Spectra ◽  
Radiation Induced ◽  
Cubic Silicon Carbide ◽  
Effect Method

The effect of 8 MeV proton irradiation on n-3C-SiC epitaxial layers grown by sublimation on semi-insulating 4H-SiC substrates has been studied. Changes in sample parameters were recorded using the Hall-effect method and judged from photoluminescence spectra. It was found that the carrier removal rate (Vd) in 3C-SiC is ~100 cm−1, which is close to Vd in 4H-SiC. Compared with 4H and 6H silicon carbide, no significant increase in the intensity of the so-called defect-related photoluminescence was observed. An assumption is made that radiation-induced compensation processes in 3C-SiC are affected by structural defects (twin boundaries), which are always present in epitaxial cubic silicon carbide layers grown on substrates of the hexagonal polytypes.

P-6H-SiC Conductivity Compensation after Irradiation of 8MeV Protons

2013 ◽  
Vol 740-742 ◽  
pp. 353-356
Author(s):  
Alexander A. Lebedev ◽  
Vitalii V. Kozlovski ◽  
Sergey V. Belov ◽  
Elena V. Bogdanova ◽  
Gagik A. Oganesyan
Keyword(s):  
Hall Effect ◽  
Irradiation Dose ◽  
Removal Rate ◽  
Initial Value ◽  
Capacitance Voltage ◽  
Full Compensation ◽  
Hall Effect Measurements ◽  
Mev Protons

Carrier removal rate (Vd) in p-6H-SiC in its irradiation with 8 MeV protons has been studied. p-6H-SiC samples were produced by sublimation in a vacuum. Vd was determined by analysis of capacitance-voltage characteristics and from results of Hall effect measurements. It was found that full compensation of samples with initial value of Na-Nd 1.5 x1018 cm-3 occurs at an irradiation dose of ~1.1 1016 cm-2. In this case, the carrier removal rate was ~130 cm-1

Comparative Analysis of Defect Formation in Silicon Carbide under Electron and Proton Irradiation

2013 ◽  
Vol 740-742 ◽  
pp. 369-372
Author(s):  
Alexander M. Ivanov ◽  
Alexander A. Lebedev ◽  
V.V. Kozlovski
Keyword(s):  
Silicon Carbide ◽  
Proton Irradiation ◽  
Defect Formation ◽  
Radiation Defects ◽  
Proton Scattering ◽  
Silicon Carbide Film ◽  
Low Energies ◽  
Simulated Distribution ◽  
Recoil Atoms ◽  
Mev Protons

The irradiation with 0.9 MeV electrons and with 8 MeV and 15 MeV protons were performed for studying radiation defects. Proton scattering in a silicon carbide film has been numerically simulated. Distribution histograms of the energy imparted to recoil atoms are obtained. Two energy ranges are considered when analyzing the histograms. In the first range of “low” energies, individual Frenkel pairs with closely spaced components are created. In the second range, recoil atoms have energies sufficient for generating a cascade of displacements. This gives rise to microscopic regions with high density of vacancies and vacancy complexes of various kinds.

scholarly journals Radiation Hardness of Silicon Carbide upon High-Temperature Electron and Proton Irradiation

Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 4976
Author(s):  
Alexander A. Lebedev ◽  
Vitalii V. Kozlovski ◽  
Klavdia S. Davydovskaya ◽  
Mikhail E. Levinshtein
Keyword(s):  
Silicon Carbide ◽  
High Temperature ◽  
Proton Irradiation ◽  
Removal Rate ◽  
Irradiation Temperature ◽  
Radiation Hardness ◽  
Main Mechanism ◽  
Deep Acceptor ◽  
High Temperature Electronics ◽  
Temperature Electron

The radiation hardness of silicon carbide with respect to electron and proton irradiation and its dependence on the irradiation temperature are analyzed. It is shown that the main mechanism of SiC compensation is the formation of deep acceptor levels. With increasing the irradiation temperature, the probability of the formation of these centers decreases, and they are partly annealed out. As a result, the carrier removal rate in SiC becomes ~6 orders of magnitude lower in the case of irradiation at 500 °C. Once again, this proves that silicon carbide is promising as a material for high-temperature electronics devices.

Comparison of the Effects of Electron and Proton Irradiation on 4H-SiC and Si Device Structures

2018 ◽  
Vol 924 ◽  
pp. 217-220 ◽  
Author(s):  
Alexander A. Lebedev ◽  
Klavdia S. Davydovskaya ◽  
Anatoly M. Strel'chuk ◽  
Andrey N. Yakimenko ◽  
Vitalii V. Kozlovski
Keyword(s):  
High Temperature ◽  
Radiation Resistance ◽  
Proton Irradiation ◽  
Removal Rate ◽  
Schottky Diodes ◽  
Simultaneous Effect ◽  
Current Voltage ◽  
Device Structures ◽  
Current Voltage Characteristics ◽  
Mev Protons

The change in the current-voltage characteristics and in Nd-Navalues in the base of 4H-SiC Schottky diodes and JBS diodes under irradiation with 0.9 MeV electrons and 15 MeV protons has been studied. The carrier removal rate for the diodes irradiated with electrons was 0.07-0.15 cm-1, and that in the case of protons, 50-70 cm-1. It was shown that the devices under study retain rectifying current-voltage characteristics up to electron doses of ~1017cm-2. It was found that the radiation resistance of the SiC-based devices significantly exceeds that of silicon p-i-n-diodes with similar breakdown voltages. The simultaneous effect of high temperature and proton irradiation on the characteristics of 4H-SiC pn structures was examined.

Effect of Powder-Mixed Dielectric on EDM Process Performance

2020 ◽  
Vol 38 (8A) ◽  
pp. 1226-1235
Author(s):  
Safa R. Fadhil ◽  
Shukry. H. Aghdeab
Keyword(s):  
Silicon Carbide ◽  
High Speed ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
High Speed Steel ◽  
Transformer Oil ◽  
Dielectric Fluid ◽  
Peak Current ◽  
Powder Concentration ◽  
Pulse On Time

Electrical Discharge Machining (EDM) is extensively used to manufacture different conductive materials, including difficult to machine materials with intricate profiles. Powder Mixed Electro-Discharge Machining (PMEDM) is a modern innovation in promoting the capabilities of conventional EDM. In this process, suitable materials in fine powder form are mixed in the dielectric fluid. An equal percentage of graphite and silicon carbide powders have been mixed together with the transformer oil and used as the dielectric media in this work. The aim of this study is to investigate the effect of some process parameters such as peak current, pulse-on time, and powder concentration of machining High-speed steel (HSS)/(M2) on the material removal rate (MRR), tool wear rate (TWR) and the surface roughness (Ra). Experiments have been designed and analyzed using Response Surface Methodology (RSM) approach by adopting a face-centered central composite design (FCCD). It is found that added graphite-silicon carbide mixing powder to the dielectric fluid enhanced the MRR and Ra as well as reduced the TWR at various conditions. Maximum MRR was (0.492 g/min) obtained at a peak current of (24 A), pulse on (100 µs), and powder concentration (10 g/l), minimum TWR was (0.00126 g/min) at (10 A, 100 µs, and 10 g/l), and better Ra was (3.51 µm) at (10 A, 50 µs, and 10 g/l).

scholarly journals Novel Abrasive-Impregnated Pads and Diamond Plates for the Grinding and Lapping of Single-Crystal Silicon Carbide Wafers

2021 ◽  
Vol 11 (4) ◽  
pp. 1783
Author(s):  
Ming-Yi Tsai ◽  
Kun-Ying Li ◽  
Sun-Yu Ji
Keyword(s):  
Silicon Carbide ◽  
Wear Rate ◽  
Single Crystal ◽  
Traditional Method ◽  
Removal Rate ◽  
Chemical Mechanical Planarization ◽  
Single Crystal Silicon ◽  
Crystal Silicon ◽  
Diamond Grit ◽  
Ceramic Binder

In this study, special ceramic grinding plates impregnated with diamond grit and other abrasives, as well as self-made lapping plates, were used to prepare the surface of single-crystal silicon carbide (SiC) wafers. This novel approach enhanced the process and reduced the final chemical mechanical planarization (CMP) polishing time. Two different grinding plates with pads impregnated with mixed abrasives were prepared: one with self-modified diamond + SiC and a ceramic binder and one with self-modified diamond + SiO2 + Al2O3 + SiC and a ceramic binder. The surface properties and removal rate of the SiC substrate were investigated and a comparison with the traditional method was conducted. The experimental results showed that the material removal rate (MRR) was higher for the SiC substrate with the mixed abrasive lapping plate than for the traditional method. The grinding wear rate could be reduced by 31.6%. The surface roughness of the samples polished using the diamond-impregnated lapping plate was markedly better than that of the samples polished using the copper plate. However, while the surface finish was better and the grinding efficiency was high, the wear rate of the mixed abrasive-impregnated polishing plates was high. This was a clear indication that this novel method was effective and could be used for SiC grinding and lapping.

Proton irradiation creep of beta-silicon carbide

2011 ◽  
Vol 418 (1-3) ◽  
pp. 198-206 ◽  
Author(s):  
Vani Shankar ◽  
Gary S. Was
Keyword(s):  
Silicon Carbide ◽  
Proton Irradiation ◽  
Irradiation Creep

Nanoparticle Fe3O4 magnetized activated carbon from Armeniaca sibirica shell for the adsorption of Hg(II) ions

BioResources ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. 6100-6120
Author(s):  
Yinan Hao ◽  
Yanfei Pan ◽  
Qingwei Du ◽  
Xudong Li ◽  
Ximing Wang
Keyword(s):  
Activated Carbon ◽  
Adsorption Capacity ◽  
Ph Value ◽  
Removal Rate ◽  
Freundlich Isotherm ◽  
Entropy Change ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Adsorption Parameters ◽  
Initial Concentration

Armeniaca sibirica shell activated carbon (ASSAC) magnetized by nanoparticle Fe3O4 prepared from Armeniaca sibirica shell was investigated to determine its adsorption for Hg2+ from wastewater. Fe3O4/ASSAC was characterized using XRD (X-ray diffraction), FTIR (Fourier transform infrared spectroscopy), SEM (scanning electron microscopy), and BET (Brunauer–Emmett–Teller). Optimum adsorption parameters were determined based on the initial concentration of Hg2+, reaction time, reaction temperature, and pH value in adsorption studies. The experiment results demonstrated that the specific surface area of ASSAC decreased after magnetization; however the adsorption capacity and removal rate of Hg2+ increased 0.656 mg/g and 0.630%, respectively. When the initial concentration of Hg2+ solution was 250 mg/L and the pH value was 2, the adsorption time was 180 min and the temperature was 30 °C, and with the Fe3O4/ASSAC at 0.05 g, the adsorption reaching 97.1 mg/g, and the removal efficiency was 99.6%. The adsorption capacity of Fe3O4/ASSAC to Hg2+ was in accord with Freundlich isotherm models, and a pseudo-second-order kinetic equation was used to fit the adsorption best. The Gibbs free energy ΔGo < 0，enthalpy change ΔHo < 0, and entropy change ΔSo < 0 which manifested the adsorption was a spontaneous and exothermic process.

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